The present invention generally relates to an apparatus for unloading small, solid components from a flexible tape carrier packaging assembly having a plurality of cavities each containing at least one component. More particularly, the present invention is directed to a method and apparatus for dispensing electrical connectors individually from a tubular passageway in a tape carrier by cutting a sidewall of the passageway, to present the connector to a wire-nesting fixture.
One known flexible tape carrier packaging assembly and ejecting apparatus is described in U.S. Pat. No. 4,631,897. A plurality of solid components, such as electrical connectors or housings for electrical components, are contained within tubular passageways of the tape carrier. An actuator arm, which may be the armature of a solenoid, is extended to enter a passageway, thereby displacing and ejecting a component. The packaging assembly is advanced through the apparatus by means in the form of indexing apertures which are engaged by teeth of a drive wheel connected to a stepping motor. In this manner, the components can be unloaded from the tape carrier package for use in a work station.
For many applications, this known technique adequately serves the single purpose of dispensing the components from the tape carrier. However, other applications require that the component be guided immediately into a component-receiving fixture for subsequent automated assembly steps. For example, many types of electrical connectors must be directly guided from the tape carrier package into a wire nesting fixture, such that wires may be affixed automatically to the connector terminals. If the wire nesting fixture cannot be located in close proximity to the tape carrier unloading machine, the connector must be transported in some manner to the fixture.
It was found that if the length of the actuator arm was extended, it also could serve as a pusher rod to transport the connector into the fixture. However, if the fixture was located twelve or more inches from the side of the tape carrier, then the length of the pusher rod had to be increased by that distance in order to guide the connector into its fixture. Moreover, if small connectors were used in such an apparatus, the pusher rod had to be very thin such that it would pass through the narrow tubular passageway in the tape carrier. For example, one connector wiring application required the use of a one-eighth inch diameter rod of approximately sixteen inches long. Such a long, thin rod was hard to accurately position within the tubular passageway, and often would bend or break. Hence, prior tape carrier unloading machines required frequent maintenance and adjustment, and were generally unreliable.
In attempting to overcome this reliability problem, it was discovered that a short pusher rod could be used if part of the/tape carrier tubular passageway was opened or cut away. A short pusher rod, having a length approximating the width of the tape carrier package, could be affixed to a larger and more substantial shuttle mechanism. Once the component was pushed out of the tubular passageway, the opening in the tape carrier would allow the shuttle to be passed over or through the tape carrier. Thus, the same short pusher rod attached to the shuttle mechanism also could be used to guide the connector into the wiring fixture.
It was further discovered that the tape carrier cutting procedure could be performed simultaneously with the removal of the component, if a knife blade tip were affixed to the shuttle mechanism. As the component was ejected from the passageway, the knife blade tip would slit the upper portion of the tape carrier in the same shuttle movement--thus permitting the shuttle to pass through the opened passageway. Only the upper tape carrier sheet was cut, since the integrity of the lower sheet had to be maintained for advancing the tape carrier and/or disposing of it. This simultaneous ejecting and cutting operation allowed small connectors to be guided more effectively and accurately into the wiring fixture, which increased the reliability of the unloading machine by allowing the use of a short pusher rod.
However, it was found that the reliability of the machine was not increased as expected. The flexible tape carrier packaging assembly would frequently buckle, fold over, or tear during the slitting operation, thereby jamming the machine and often damaging the fragile connectors. The tape carrier buckling problem was much worse when new tape carrier materials, which are stronger yet thinner and more flexible, were used. The unloading machine was particularly unreliable when tape carriers were used.
A need, therefore, exists for providing a reliable and efficient technique for unloading components from tape carrier packaging assemblies.